With growing concerns about the effects of global warming on polar bears, it's increasingly important to understand how other environmental threats, such as mercury pollution, are affecting these magnificent Arctic animals.

Although most wolves in Yellowstone National Park live to be nearly six years old, their ability to kill prey peaks when they are two to three, according to a study led by Dan MacNulty and recently published online by Ecology Letters.

President Obama designated more than 200,000 square miles in Alaska and off its coast as "critical habitat" for polar bears on Thursday, an action that could add restrictions to future offshore drilling for oil and gas.

A mother bear and one of her three cubs, apparently looking for food, repeatedly tried to enter a grandmother's Colorado home, the resident said.
Sally Rebehn of Vail, Colo., said the mother bear broke into her bedroom, but Rebehn fended it off with a decorative pillow, KMGH-TV, Denver reported.
The mother bear and the baby bear then entered the kitchen and enjoyed ice cream, chili and their favorite -- leftover barbecued chicken wings from Moe's Barbecue, Rebehn said.
The ice cream was too...

The cave bear (Ursus spelaeus) is an extinct species that was found in Europe during the Pleistocene. Its range was large and included areas from Great Britain to Spain, Italy, Poland, the Balkans, areas of Germany, Russia, the Caucuses, Romania, and northern areas of Iran. Large numbers of skeletons have been found in Switzerland, southern Germany, Austria, northern Spain, Hungary, Croatia, and Romania. Because so many fossils have been found throughout Europe, some experts assert that there...

The Kodiak bear (Ursus arctos middendorffi), also known as the American brown bear, the Kodiak brown bear, or the Alaskan grizzly bear, is a subspecies of the brown bear. It can be found in southwestern Alaska, on the islands of the Kodiak Archipelago. Most coastal bears that occur in Alaska are called Kodiak bears, but the true Kodiak bear only inhabits the islands of the Kodiak Archipelago.
The Kodiak bear was first described as a distinct species by the taxonomist C.H. Merriam. Merriam...

The grizzly bear (Ursus arctos horribilis), also known as the grizzly, the North American brown bear, or the silvertip bear, is one of many subspecies of the brown bear. It is typically found in upland areas of western North America. Its range once extended from Canada to Mexico and even into the western shores of the Hudson Bay in the east. Its range has been reduced to many areas of Canada, Alaska, and northwestern areas of the United States including Washington, Wyoming, Idaho, and...

The Asian black bear (Ursus thibetanus), also known as the white-chested bear or the moon bear, is a species that holds a large range. This range includes northern areas of the Indian Subcontinent, most areas of the Himalayas, far eastern Russia, northeastern areas of China, Korea, and the Honshū and Shikoku islands near Japan. As is common to black bear species, the Asiatic black bear prefers a habitat within deciduous forests, mixed forests, deserts, and thornbrush forests. It can...

The cave bear (Ursus spelaeus) is an extinct species that was found in Europe during the Pleistocene. Its range was large and included areas from Great Britain to Spain, Italy, Poland, the Balkans, areas of Germany, Russia, the Caucuses, Romania, and northern areas of Iran. Large numbers of skeletons have been found in Switzerland, southern Germany, Austria, northern Spain, Hungary, Croatia, and Romania. Because so many fossils have been found throughout Europe, some experts assert that there...